docs: def apt_purge(packages, fatal=False):
      """Purge one or more packages."""
      cmd = ['apt-get', '--assume-yes', 'purge']
      if isinstance(packages, six.string_types):
          cmd.append(packages)
      else:
          cmd.extend(packages)
      log("Purging {}".format(packages))
      _run_apt_command(cmd, fatal)